This paper describes an application of the theory of self-heating and thermal explosion of the spontaneous ignition of potato chip waste. Long term heating experiments were carried out in thermostats over the temperature range of 30-140°C in an air atmospher. Sample potato chips were set in spherical stainless stell cages of 6, 15, 20, 30, 40, 50, and 70cm diameter and their temperature changes were monitored. Physical parameters of apparent activation energy, and overall heat of reaction value were also estimated by TG-DSC analysis. Thermal conductivity of the bulk sample was measured independently. The correlations between ambient temperature and bulk size of the chips, which lead to the spontaneous-ignition, were estimated experimentally and by theoretical calculations. The estimations showed close coincidence with each other.

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This paper reports the velocity dependent nature of the effective operating temperature of a liquid-in-glass type of sprinkler head. Experimental studies is carried out using a specially designed heated wind tunnel for studying thermal responses of sprinkler heads. The tunnel is similar to the one developed at the Fire Research Station, United Kingdom. With it, two tests: plunge and ramp test, are carried out to investigate the thermal responses of the sprinkler head. Especially, thermal responses at low air speed are investigated in details. About one hundred sprinkler heads are studied and results on different defined time indices are correlated with this fairly large sample size.

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2-dimensional numerical computations of the fire induced convective heat flow in an atrium have been done using a pseudo K-ε flow model of a viscous heat conducting compressible fluid. The size of the atrium is 30 m high and 30 m wide, with a 3 m high doorway at the bottom of the wall.
The effect of pre-fire temperature stratification which can be formed by normal air-conditioning has been considered. Prior to the simulated fire initiation, the stratified environment is calculated numerically with the pseudo- K-εfield model. The initial conditions of the pre-fire computation are set as that the air in the atrium is initially motionless with uniform temperature of 20°C. The solid boundary has been divided into two parts. The temperature of the ceiling and the walls of the upper part has been set as 40°C, and the temperature of the floor and the lower wall has been set as 20°C.
After a steady state is attained in the pre-fire calculation, a fire-simulating heat source is placed at the center of the floor. The initial temperature is set as 20°C and then its temperature is increased linearly unit 800°C in 5 minutes and then kept constant.
As a results of the computation, it has been found that the ceiling-mounted heat detectors or smoke detectors may not respond to the early stage of the fire occurred in a temperature stratified high atrium. The pre-existing hot temperature layer may so inhibit penetration of the smoke flow that the initial smoke layer is formed not adjacent to the ceiling but under this hot layer. Thus ceiling-mounted smoke detectors or heat detectors may not provide early stage fire detection in high atria with air-conditioning.

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